Since July 7, the U.S. Education Department’s Office of Civil Rights has been investigating whether the district’s “One Newark” plan to reorganize schools discriminates against black students, spokeswoman Dorie Turner Nolt said. She said additional information couldn’t be released because the investigation is ongoing.

Parents and a national civil rights organization filed the complaint in May against the plan to consolidate or relocate almost a third of the city’s schools. The plan also would convert two neighborhood district schools into charter schools. And it would allow parents to use one application to apply to either.

The district didn’t immediately return a call for comment.

The state took over control of Newark’s schools in 1995, but the state Board of Education voted last month to return financial control to the district’s advisory school board. Parents in Newark had sued after the state refused to return local control in areas where the 40,000-student district had shown success.

State-appointed Superintendent Cami Anderson’s plan to overhaul the district didn’t need formal approval from the board. The district says the “One Newark” plan aims to guarantee that all students in the district attend high-performing schools, using the same standards for public and charter schools.

The complaint says black students make up 51 percent of the district, but 86 percent of students affected by the plan are black. It says white students make up 8 percent of the district, but less than 1 percent are affected.

The Journey for Justice Alliance and the Advancement Project wrote in a letter to U.S. Attorney General Eric Holder and Education Secretary Arne Duncan that “education ‘reformers’ and privatizers are targeting neighborhood schools filled with children of color, and leaving behind devastation.”

“By stealth, seizure, and sabotage, these corporate profiteers are closing and privatizing our schools, keeping public education for children of color, not only separate, not only unequal, but increasingly not public at all,” the groups wrote in the May letter.